Structural Studies of the BRCA1-Associated Human SWI/SNF Complex
Abstract
Mutations in the tumor suppressor gene, BRCA1, account for 45% of families with a high incidence of breast cancer and the majority of families with high incidences of both breast and ovarian cancers. Recent data has shown BRCA1 to be associated to be associated with a human SWI/SNF complex, serving to link breast cancer to chromatin remodeling (3). Current evidence points to the idea that BRCA1 works through SWI/SNF; therefore, a molecular understanding of the SWI/SNF complex and other human chromatin remodeling complexes will offer insight into the biology of BRCA1. The central catalytic ATPase subunit of SWI/SNF is BRG1; the central catalytic subunit of a related human chromatin-remodeling complex, NURF, is SNF2H. Initially, crystallization and X-ray structural determination of the core AThase domain in addition to the full-length proteins was undertaken with much difficulty. Currently crystals have been grown for the AThase domain of Brgl and crystallization trials are underway for the related full-length human protein, SNF2H. Initial purification and expression of a SWI/SNF functional core and the SNF2H containing NURF complex were unsuccessful. The conserved core ATPase domain was identified in two organisms that are more primitive. A recombinant homologous ATPase domain from both organisms was expressed, purified, and three-dimensional crystals were grown. Optimization and refinement of these initial crystals was underway to obtain X-ray diffraction quality crystals for structural determination of these homologous archaeal ATPase domains, but were derailed by a recently published X-ray structure of the Sulfolobus sulfataricus SWI2/SNF2 ATPase core and its complex with DNA (18).
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2005
- Accession Number
- ADA436926
Entities
People
- Marc A. Holbert
Organizations
- University of Pennsylvania